Our nearest evolutionary ancestors, the Neanderthals, existed for 400,000 years, during which time they successfully inhabited less than 10% of Earth's landmass. They lived primarily in Europe, Western and Central Asia, extending into southern Siberia. Their highest densities were in France, Spain, and Italy. Homo Sapiens, our species, has existed for 300,000 years. In that time, we have managed to inhabit 90-95% of Earth's land surface. The only areas safe from us are Antarctica and other harsh, high-elevation regions. Antarctica is kept pristine with the help of international treaties. The highest elevations are by practicality. It is hard to survive in brutal cold, especially when ensuring access to food and water.